Note 3 - Supplemental Balance Sheet Information - Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Intangible assets	$ 4,781	$ 5,833
Less accumulated amortization	(3,601)	(3,793)
Intangible assets, net	1,180	2,040
Customer Contracts And Lists [Member]
Intangible assets	3,011	3,543
Trade Names [Member]
Intangible assets	900	900
Patents [Member]
Intangible assets	870	870
Noncompete Agreements [Member]
Intangible assets	$ 0	$ 520

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Topic 210
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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